Childhood obesity assessment and staged management OSCE — classification, comorbidity screening and weight-neutral planning

Station objectives

1. Classify childhood obesity using BMI-for-age and identify severe-obesity thresholds and the adult crossover. [1]
2. Screen systematically for comorbidity across six systems and order the baseline panel. [1] [2]
3. Exclude secondary and syndromic causes selectively, guided by red-flag features. [2]
4. Deliver weight-neutral lifestyle counselling using motivational interviewing and build a staged management plan with parallel comorbidity-directed care. [1] [5]

Candidate brief

You are the paediatric doctor in the endocrinology clinic. You have 10 minutes for Station A (classification and family counselling) and 12 minutes for Station B (severe obesity with comorbidity and integrated management planning). Examiners score clinical reasoning, communication, weight-neutral counselling quality, comorbidity-directed planning, and safety awareness. [1]

Station A — Classification and the father's question

Setup: A 10-year-old boy attends with his father. His BMI plots above the 97th percentile, and he has acanthosis nigricans. The father, who has type 2 diabetes, asks directly, "Is he obese and sick, and what do we do?" [2]

Expected actions:

• Acknowledge the father's concern and validate his desire to help without confirming blame. [2]
• Classify the weight status correctly: BMI above the 95th percentile meets obesity; calculate the percentage of the 95th percentile to assess severe obesity. [1]
• Explain in biologically accurate terms that obesity is a chronic disease of excess adiposity with a polygenic basis and regulated appetite signalling, not a willpower failure. [2]
• Order the baseline comorbidity panel — fasting glucose or HbA1c, lipids, ALT, blood pressure — and introduce the staged approach in plain family language. [1]
• Use weight-neutral, person-first language throughout and never direct the word "obese" at the child. [1]

Station B — Severe obesity, comorbidity and integrated planning

Setup: A 15-year-old girl has a BMI of 38 kg/m² with newly diagnosed impaired glucose tolerance and a persistently elevated ALT. She reports low mood and weight-based bullying. Her mother asks whether anything beyond diet and exercise can help. [5]

Expected actions:

• Recognise severe obesity with comorbidity and justify Stage 3 pharmacotherapy and Stage 4 surgical consideration, citing the GLP-1 receptor agonist trials and the Teen-LABS surgical evidence. [13] [6]
• Treat the impaired glucose tolerance with metformin alongside lifestyle, and address the elevated ALT per the NASPGHAN guideline with ultrasound and gastroenterology referral, recognising that ultrasound is insensitive for early steatosis. [7]
• Screen mood and eating behaviour with validated tools, and build a staged, weight-neutral plan that integrates psychology input and addresses the weight-based bullying with the school. [1]
• Measure success through health behaviours, comorbidity resolution and psychosocial function rather than the scale alone, and plan a structured transition to adult care from late adolescence. [1]

Marking anchors

Clear pass: correct BMI-for-age classification with severe-obesity threshold identified, biologically accurate disease framing that defuses blame, complete baseline comorbidity panel ordered, weight-neutral counselling without weight-centric language, staged plan with parallel comorbidity-directed care, and evidence-based justification of pharmacotherapy and surgery. [1] [5] [13] [6] Borderline: knows the BMI cut-off but cannot explain the severe-obesity threshold, or orders good counselling but omits the comorbidity panel or the ALT follow-up pathway. [1] [7] Fail: confirms the father's willpower framing, uses stigmatising language, prescribes a restrictive diet that ignores eating-disorder risk, or fails to investigate a comorbidity flagged on screening. [2] [7]

Debrief pearls

• The BMI number opens the conversation; it never closes it. [1]
• Treat comorbidities in parallel with the weight intervention — the comorbidity burden is what makes obesity a disease. [1] [7]
• Weight-neutral language and person-first phrasing are scored communication domains, not optional courtesies. [1]
• GLP-1 receptor agonists and surgery are evidence-based for severe disease; do not leave severe obesity on lifestyle alone. [13] [6]